Station Crew Awaiting Arrival of Final Shuttle

On Tuesday, after a three-day weekend of light duty, the six-member Expedition 28 crew tackled some of the 111 experiments aboard the orbiting International Space Station and entered the home stretch of preparations for the arrival of space shuttle Atlantis.

All three cosmonauts aboard the station – Commander Andrey Borisenko and Flight Engineers Alexander Samokutyaev and Sergei Volkov – began their workday by participating as subjects in a study of cardiac bioelectric activity at rest. Afterward, the two Russian flight engineers spent some time swapping out hoses and a “pre-treat” unit for the Russian toilet, which went down over the weekend but did not impact operations.

Meanwhile, Flight Engineer Satoshi Furukawa of the Japan Aerospace Exploration Agency pre-packed items for return to Earth aboard Atlantis. The space shuttle and its four-member STS-135 crew are set to launch Friday at 11:26 a.m. EDT and dock with the station Sunday, July 10. Atlantis will deliver the Raffaello multi-purpose logistics module packed with about 8,200 pounds of supplies and spare parts to sustain station operations beyond the shuttle’s retirement.

Furukawa also set up a test sample for a Japanese experiment that studies how plants sense gravity as an environmental signal and use it for governing their morphology and growth orientation.

NASA astronauts Mike Fossum and Ron Garan, both flight engineers, continued preparations for the spacewalk they will conduct while Atlantis is docked with the station. Fossum initiated a recharge of spacesuit batteries, and he and Garan participated in a session of onboard training for Simplified Aid for EVA Rescue, or SAFER. Should a spacewalker become untethered during a spacewalk and begin floating away, the small nitrogen-jet thrusters of SAFER could propel the astronaut back to the station.

Additionally, Garan performed maintenance on the Major Constituents Analyzer (MCA) as he continued the removal and replacement of that unit’s failed Mass Spectrometer Assembly. Work with the unit was delayed from Friday due to a time-consuming issue with some fasteners. The MCA monitors the station’s atmosphere continuously for oxygen, nitrogen, carbon dioxide, hydrogen, methane and water vapor levels. The failed component will be returned to Earth aboard Atlantis for further study.